Objective To investigate social mental risk factors of breast cancer (BC) patients and provide a theoretical basis for their psychological intervention.

Methods With a 1:1 matched-pair case-control study design, a total of 134 BC patients and 134 healthy women were investigated by self-designed general demographic questionnaire, Pittsburgh Sleep Quality Index (PSQI) questionnaire, occupational stress questionnaire, coping style scale, and social support scale.

Results The scores of sleep quality, sleep time, sleep disorder, daytime dysfunction, PSQI, and negative coping in the BC patients were significant higher than those in the controls (P<0.05); the scores of social support dimension, subjective support, support utilization, and social support scale total were lower (P<0.05); and the scores of other dimensions and relevant total were not statistically different (P>0.05). The results of unconditional logistic regression analysis showed that the protective factors of BC were sleep time, social support, and support utilization (OR=0.547, 0.495, and 0.697; 95%CI:0.310-0.967, 0.245-0.997, and 0.591-0.821) and risk factors were sleep disorders, positive coping, and objective support (OR=4.619, 1.053, and 1.379; 95%CI:2.406-8.866, 1.000-1.108, and 1.177-1.615).

Conclusion Sleep quality, occupational stress, coping style, and social support could be associated with the incidence of breast cancer.